In this study, various types of reactors were employed to investigate chitinolytic enzymes production via Paenibacillus taichungensis. It was found that the net-draft tube air-lift reactor (ALNR) gave the best performance among the reactors. Different aeration conditions of ALNR were carried out to evaluate cell growth and chitinolytic enzymes production. It was found that a 2 vvm aeration produces an optimal chitinolytic enzymes activity level of 21.1 mU/mL, which was 2.6 times greater than that obtained in a stirred-tank reactor. To explore the result, the shear rates and oxygen transfer rates of both reactors were evaluated and compared. Meanwhile, the morphologies of the strain for chitinolytic enzymes production were also investigated. (C) 2010 Elsevier B.V. All rights reserved.